Most corporations that do regular random drug screens, the police, and the courts have relied on the validity of research that claims the presence of THC in hair follicles is absolute proof of marijuana use. Professor Volker Auwrter, forensic toxicologist at the Institute of Forensic Medicine in Freiburg, Germany, and colleagues have proven the basis for assuming the use of marijuana from the presence of THC in hair to be totally invalid. The research was reported in the Oct. 7, 2015, edition of the journal Scientific Reports of the Nature Publishing Group.
The researchers proved that the analog of THC that is tested for in the hair test that has been presumed to be an infallible proof of the use of marijuana can be transferred to a person that did not use pot through the sweat or skin oil of a person that did use pot. Hair replaced urine as a test media for the use of marijuana because it was too easy for users to beat the urine test with clean urine. The researchers also proved beyond any reasonable doubt that exposure to marijuana smoke in a passive environment could produce a positive test for pot use in the hair of people that did not smoke marijuana. Repeated washing will not remove the THC from hair.
The researchers indicate that their findings will have a great influence on child custody battles in Germany. The thousands of people that lost their jobs because of a positive test for marijuana using a hair sample now have legal recourse to sue for back wages and pain and suffering. One might expect a marijuana advocacy group to file a class action suit in the United States on the basis that the hair test for marijuana use is absolutely invalid. One would not be surprised to find out that the police, courts, and people that use the hair test for marijuana use knew the test was invalid a long time ago. Hair testing was supported because the test was assumed to be valid for as long as 90 days provided the hair sample was at least 1.5 inches in length.
